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Abstract  

High-level radioactive wastes can be transformed to low-level wastes by removing137Cs through selective ion exchange processes. Since the short-lived daughter,137inBa produces the 662-keV gamma-ray normally attributed to137Cs, equilibrium may be broken, and observation of the 662-keV gamma-ray cannot be used to detect cesium breakthrough. Two detectors viewing the output line, but separated sufficiently to measure the137mBa decay between them, are used to detect137Cs breakthrough based on deviation from the normal137mBa decay. Detection evaluated for the process separation time, counting time, fractional breakthrough detectable, and accuracy and confidence of the measurements are discussed.

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Abstract  

This study investigates uptake of cesium and strontium from aqueous solution similar to nuclear waste on three samples of titanium molybdophosphate (TMP) synthesized under various conditions. Effects of concentration of sodium nitrate, pH and contact time on the uptake of cesium and strontium have been studied by bath method. The results showed that TMP has high affinity toward cesium and strontium at pH > 2 and relatively low concentration of sodium nitrate. Kinetic data indicated that cesium uptake process to achieve equilibrium was faster than strontium. Cesium and strontium breakthrough curves were examined at 25 °C using column packed with H3O+ form of TMP and breakthrough curves showed symmetrical S-shaped profiles. At the same time, the calculated breakthrough capacity for cesium was higher than strontium. The results of desorption studies showed that over 99% of cesium and strontium was washed out of column by using 4 M NH4Cl solution. This study suggests that TMP can have great potential applications for the removal of strontium and specially cesium from nuclear waste solution.

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Abstract  

The Wheeler–Jonas equation (WJ equation) is widely used to predict breakthrough of volatile organic compounds on granular activated carbon (GAC) and the most important criteria is to calculate the overall adsorption rate constant (k v) and amount adsorbed based on breakthrough curve. The operational factors, including temperatures, concentrations and flow rates, for packed bed, can affect the values of k v more or less and to what degree has not yet been systematically investigated. What’s more, the relation between the dynamic adsorption coefficient (k d) or Henry constant, which is used for the design of packed bed, and WJ equation is not clear. In order to solve these problems, we performed xenon dynamic adsorption on GAC adsorber experiments under different values of xenon concentrations, flow rates and temperatures, obtained the breakthrough curves for elution times versus xenon concentrations, and then employed WJ equation to explain breakthrough curves. The experimental results indicate that the WJ equation can fit the breakthrough curve very well and k d be integrated into the WJ equation. The values of k v are proportional to the values of flow rates and k d, but independent of that of temperatures and xenon concentrations.

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In the economic growth process when China joined in WTO, internationalized operation has become an inevitable issue. Under the new normal economic condition, including the cut offtariffs on imported goods, businesses in China have realized the importance of enhancing the overall brand image, quality of products and services, and the international compatibility. Businesses of China need to develop creative and high-value-added products, and shall be able to rapidly change to satisfy market requirements to distinguish themselves from other products. It is the way of creating a new pattern of upgrading. It is the market-orientated development that is a primary condition for enterprises to adapt to the rapidly changing environment, keeping growth and attracting customers, acquiring competitive advantages, and creating excellent value for customers. It reveals the fact that in the future, businesses must change the focus from product to market needs. It is the marketorientation which could generate the competitive strength to resist competitors.

The research involves in total 45 international enterprises, which are distributed with the questionnaires. There are totally 124 and 107 copies of questionnaires retrieved from manufacturing industry and service industry, with valid retrieval rates of 54% and 46%, respectively. The research results show that: 1. there is positive effect of market orientation on breakthrough innovation, 2. there is positive effect of breakthrough innovation on organizational performance, and 3. there is positive effect of market orientation on organizational performance. Based upon the results, some suggestions are proposed in this study, expecting to help international enterprises develop market orientation, enhance breakthrough innovation, and improve organizational performance.

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Abstract  

There is general consensus that the field of nanotechnology will be very important in the future. An open question is, however, which technological approaches or paradigms will be important in the field. The paper assumes that the carbon nanotube will be a key element of an emerging technological paradigm in nanotechnology. This study employs a bibliometric method — bibliographic coupling — to identify important nanotubes-related ‘leitbilder’ — a concept meaning ‘guiding images’ that provide a basis for different professions and disciplines to work in the same direction. Until recently, bibliographic coupling has been applied rarely for purposes of research evaluation, not to mention technology foresight. Our case study seems to suggest that bibliographic coupling is particularly suitable for anticipating technological breakthroughs. Bibliographic coupling analysis of recent nanotube-related patents focused our attention to recent patents owned by Nantero Inc. Nantero’s main focus is the development of NRAM — a high-density nonvolatile random access memory. The NRAM leitbild seems to be an important emerging leitbild. It connects technical opportunities and promising applications relating to the memories in devices such as cell phones, MP3 players, digital cameras, as well as applications in networking arena.

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Abstract  

The breakthrough volumes on Reillex-HPQ anion exchange resin columns for TcO 4 solutions have been determined. The feed solutions were a Handford Double Shell Tank Slurry (DSS) simulant of ionic strength () of 6.22 M and a TcO 4 of 5.00×10–5 M and a 13 dilution of the DSS simulant, =2.07 M, with a TcO 4 of 1.67×10–5 M. The DSS flow rates {mL simulant/(cross section area of column.min)} through the column varied from 0.19 to 20.5 cm/min. The 1% breakthrough volumes varied from 50.0 to 1.3 bed volumes (BV), respectively. The 13 DSS flow rate varied from 0.95 to 11.0 cm/min and had 1% breakthrough volumes ranging from 94 to 20 BV, respectively. At a flow rate of 1.0 cm/min, the breakthrough bed volumes are 10.2 and 95.8 BV for the DSS and 13 DSS solutions, respectively. Obviously, there is an advantage in processing the 13 dilution of the feed stream.

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Abstract  

Five column experiments have been carried out to investigate the effect of flow rate on the breakthrough curves (BTCs) of phosphate, fulvic acid, and uranium(VI) onto a silica column. Both BTCs of phosphate and fulvic acid, and three BTCs of uranium(VI) in the presence and absence of phosphate or fulvic acid at high flow rate published in the previous paper [<cite>1</cite>] were compared with corresponding initial parts of BTCs at low flow rate in this paper. Each BTC in this paper was expressed as both C/Co–t and C/Co–V/Vo plots, where C and Co are the concentrations in the influent and the effluent respectively, t and V are the time and the effluent volume from the start of injection of pulse solution respectively, Vo is the pore volume of the SiO2 column. Based on the experimental results and the relationship among V, t, and flow rate F, it was found that there are advantages to using C/Co–V/Vo plot as BTC to study the effect of flow rate. Based on these comparisons of C/Co–V/Vo plots at different flow rates and the theoretical analysis from the Bohart–Adams sorption model, it was found that the right shift (increase in V/Vo of breakthrough), the left shift (decrease in V/Vo of breakthrough), and the non-shift (non-change in V/Vo of breakthrough) of initial parts of BTCs with increasing flow rate are certain to occur instead of only left shift and that three different trends of shifts can be mainly attributed to different rate-controlling mechanisms of sorption process.

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Abstract

This paper presents an in depth study of an interesting analogy, recently proposed by Prathap (Scientometrics 87(3):515–524, ), between the evolution of thermodynamic and bibliometric systems. The goal is to highlight some weaknesses and clarify some “dark sides” in the conceptual framework of this analogy, discussing the formal validity and practical meaning of the concepts of Energy, Exergy and Entropy in bibliometrics. Specifically, this analogy highlights the following major criticalities: (1) the definitions of E and X are controversial, (2) the equivalence classes of E and X are questionable, (3) the parallel between the evolution of thermodynamic and bibliometric systems is forced, (4) X is a non-monotonic performance indicator, and (5) in bibliometrics the condition of “thermodynamic perfection” is questionable. Argument is supported by many analytical demonstrations and practical examples.

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://www.fda.gov/Drugs ) was used for the drug selection. Two groups of 10 drugs were used to test the first hypothesis. One group included the most successful (breakthrough) drugs belonging to various pharmacological classes (1st column in Table 1 ). The drugs in this group

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